Door structure



Dec. 1, 1964 M. ROSENFELD DOOR sTRubTuRE Filed Oct. 9, 1961 INVENTOR.

MORTON M. ROSENFELD BY M ATTORNEY 3,159,093 Patented Dec. 1, 1964 United States Patent Ofiice 3,15%93 D0918. STRUCTURE Morten M. Rosenfeid, Mount Vernon, NY. (271 Madison Ave, New York, NY.) Filed Get. 9, 19d1, Ser. No. 143367 Claims. (CI. 9887) This invention relates to a door structure. More particularly, this invention relates to a door structure wherein a door is mounted in a door frame in the manner so that a space is provided between the door frame and the periphery of said door for passage of air therebetween by a circuitous path.

In many environments, such as jails, bombshelters, etc., there is a need for a door which provides for ventilation by means of a circuitous path while at the same time being sufiiciently strong so as to accomplish its intended function. A door of this nature is particularly adaptable for use in bombshelters or the like. Gamma rays from a nuclear blast travel in straight lines. Accordingly, the ventilation for a bombshelter should include a circuitous path.

The door structure of the present invention provides a circuitous path around the periphery of the door in a manner which is simple, effective and inexpensive. The door structure of the present invention includes a door reinforced with steel plates or the like and is devoid of any apertures or opening through which the barrel of a rifle may be extended so as to force persons on the other side of the door to open the same. 7

It is an object of the present invention to provide a door structure which is structurally interrelated with a door frame so as to provide for ventilation by means of a circuitous path.

It is another object of the present invention to provide a substantially imperforatc door for use in bombshelters or the like.

It is another object of the present invention to provide a door structure which permits ventilation by a circuitous path while discouraging forcible entry.

Other objects will appear hereinafter.

For the purpose of illustrating the invention there is shown in the drawings a form which is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.

FIGURE 1 is a partial front elevational view of a bombshelter incorporated in the door structure of the present invention.

FIGURE 2 is a sectional view taken along lines 2-2 in FIGURE 1.

FIGURE 3 is a rear elevational view of a door structure illustrated in FIGURE 1.

FIGURE 4 is a sectional view taken along the lines 44 in FIGURE 3.

FIGURE 5 is a sectional view of a portion of a door in accordance with another embodiment of the present invention.

Referring to the drawing in detail, wherein like numerals indicate like elements, there is shown in FIGURE 1 a portion of a bombshelter designated generally as 10.

The portion of the bombshelter illustrated in FIG- URE 1 includes a rectangular door frame 12 mounted in an opening 14 in wall 16. A shown more clearly in FIGURE 2, the door frame 12 is L-shaped in transverse cross-section. Thus, the door frame 12 includes a leg 18 which is secured to the wall 16 by a plurality of bolts at spaced points therearound and a leg 20 which is perpendicular to the leg 18.

The door frame 12 is rectangular in shape with each of the top, bottom, and side portions being identical in transverse cross-section. The legs 20 on the top, bottom, and side portions defines a rectangular opening 22 as shown more clearly in FIGURES 1 and 3. A door 24 having an outer periphery slightly larger than the opening 22 is pivotably mounted within the door frame 12. The door 24 includes a layer of wood 28 and a layer of plate steel 26.

The layer of plate steel 26 is provided with an integral flange 27 extending substantially perpendicular to the plane thereof. The flange 27 is disposed within a mating recess on the periphery of the layer 28. A plurality of bolts extend through the flange 27 into the layer 28 thereby securing the layer of steel plate 26 to the layer of wood 28. The door 27 is pivotably mountedto the door frame 12 by means of hinges 30 and 32 on one side thereof. One-half of the hinges is bolted to the leg 18 and the other half is bolted to the flange 27. It will be noted that the manner in which the hinges are mounted, the manner in which the layer of steel plate 26 is secured to the layer of Wood 28, and the manner in which the door frame 12 is secured to the wall 16 is not readily ascertainable and discourages forceful entry since the bolts are not readily accessible when the door 24 is in a closed disposition.

As shown more clearly in FIGURES 1 and 2, the rear surface of the door 24 is provided with a plurality of spaced limit stops 34 projecting from its surface. As illustrated, three such limit stops are provided. A larger or lesser number of limit stops may be provided if desired. The provision of the limit stops 34 and the relative sizes of the door 24 and frame 12 results in a rectangular opening 35 between the periphery of the door 24 and the door frame 12. In transverse cross section, the opening 35 is L-shaped. The opening 35 performs the function of providing ventilation for the interior of the bombshelter 1%. At the same time, the L-shape of the opening 35 prevents gamma rays from entering the bombshelter 10. It will be noted that the shape of the opening 35 prevents a person from sticking the barrel of a gun therethrough and forcing a person on the other side of the door 24 to open the same.

The limit stops 34 are preferably coil spring. The coil springs have high strength so as not to be compressed during ordinary use of the door 24. The coil springs will permit the door 24 to move inwardly and arbsorb shock waves from an explosion, earthquake, etc. and prevent a blast wave from entering the shelter.

To facilitate the opening and closing of the door, the door 24 is provided with a handle 36 on one side and a handle 38 on the other side. To facilitate locking the door 24, the leg 29 of the door frame 12 may be provided with a flange 40. A pair of spaced ears 42 and 44 extend from the flange 40 to a point within the opening 22. An car 46 extends from the layer of wood 28 in a disposition so as to be disposed between the ears 42 and 44. Each of the cars 42, 44 and 46 are provided with an elongated hole. The holes in the ears 42, 44 and 46 are in alignment in the closed disposition of the door 24. A bolt 48 having a head thereon may extend through the aligned holes so as to prevent the door 24 from being opened. It will be obvious to those skilled in the art that other locking means may be substituted. For example, a padlock or cross bar device may be substituted for the bolt 48.

While the door 24 may be solid, it is illustrated as having a pair of horizontally disposed slots 58 and 52. As shown more clearly in FIGURE 4, the slots 50 and 52 are Z-shaped in transverse cross section. The slots 5i md 52 provide additional air vents and thus supplement the opening 35 in this regard. The shape of the slots 56 and 52 prevents gamma rays, foreign articles, etc. from passing therethrough. If desired, a larger number of slots such as with respect to the plan of the door 24-. The Z-shape of the slots and 52 facilitate the provision of mirrors 54 and 56 so that the door 24- has a periscope therein.

While the door structure of the present invention has been illustrated as being incorporated in a bombshelter, it will be appreciated that the door structure may be utilized in any one of a variety of enclosures wherein a strong reinforced door is required and it is desired to provide ventilation bymeans of a circuitous path. The door frame 12, hinges 3d and 32, and plate 26 are all mounted in a manner which discounages tampering therewith. Thus, it will be seen that the door structure may be utilized in a prison, Stockade, etc. As a general rule, the width of the opening 35 depends upon the number of persons disposed within the enclosure of which the Wall 16 forms a part. In a bombshelter adapted to be utilized by an average family, the width of the opening 35 is preferably about two inches.

While the door 24 and frame 12 are illustrated as being rectangular in shape, it will be obvious that other shapes may be utilized. It will be noted that the bottom port-ion of the frame 12 acts as a water barrier to a limited extent.

As described above, the door 24 includes a layer of wood 28 and a layer of plate steel 26. It is within the scope of the present invention to increase the shielding ability of the door 24. This may be accomplished by making the door 24 from a mixture of concrete, a boron compound and aggregates of an elemental heavy metal. A suitable boron compound would be borax or colcmanite. Carbon in the form of pulverized coal may be used instead of the boron compound. Steel turnings and the like may be the aggregates of an elemental heavy metal. The mixture may include a uniform dispersion of a heavy metal oxide such as hematite, limonite or red lead (Pb O If desired, the door 24 may be solid steel or may be a door 24' having a steel plate over a concrete mixture as set forth in the next preceding paragraph and illustrated in FIGURE 5. That is, the said concrete mixture may be substituted for the layer 28 of wood. When the door 24 is made of a concrete mixture having high shielding qualities, the wall16 is preferably made of the same materials so that the bomb-shelter will have uniform neutron shielding qualities. v i

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification as indicating the scope of the invention.

* I claim: I

1. Apparatus comprising a wall having a door opening, a door frame in said opening, said door frame defining an opening through which persons may pass, hinge means pivotally mounting a door to said door frame for selectively blocking the opening in said door frame, resilient means maintaining a space between said door and an inner portion of said door frame for passage of air between said door and said door frame by a path which does not permit air to pass directly through in a direction perpendicular to the plane of said door 'in its closed disposition.

2. Apparatus in accordance with claim 1 wherein the shape of said door frame opening is substantially identical to the shape of said door, and the periphery of said door being slightly larger than the inner portion of said door frame opening.

3. Apparatus in accordance with claim 2 wherein said door frame is L-shaped in transverse cross-section so as to have a first leg substantially perpendicular to the plane of said door in its closed disposition and a second leg substantially parallel to the plane of said door in its closed disposition, said resilient means spacing said door from said second leg in the closed disposition of said door,

whereby said space between said door frame and the periphery of said door for passage of air therebetween is L-shaped in transverse cross-section.

4. Apparatus in accordance with claim 2 wherein said door includes a flat layer of steel plate, said hinge means including hinges secured to said first leg ofsaid door frame so that said door is pivotable for movement toward and away from the plane of said door frame.

5. Apparatus in accordance with claim 2 wherein said door is imperforate, and said hinge means are secured to said door and said door frame so that said door may pivot toward and away from the plane of said wall.

References Cited in the file of this patent f UNITED STATES PATENTS OTHER REFERENCES Publication 1: Curtis Design Book of Architectural Woodwork (issue of February 1, 1946, page 82, copy available in Division 49, class 98-87). 

1. APPARATUS COMPRISING A WALL HAVING A DOOR OPENING, A DOOR FRAME IN SAID OPENING, SAID DOOR FRAME DEFINING AN OPENING THROUGH WHICH PERSONS MAY PASS, HINGE MEANS PIVOTALLY MOUNTING A DOOR TO SAID DOOR FRAME FOR SELECTIVELY BLOCKING THE OPENING IN SAID DOOR FRAME, RESLILIENT MEANS MAINTAINING A SPACE BETWEEN SAID DOOR AND AN INNER PORTION OF SAID DOOR FRAME FOR PASSAGE OF AIR BETWEEN SAID DOOR AND SAID DOOR FRAME BY A PATH WHICH DOES NOT PERMIT AIR PASS DIRECTLY THROUGH IN A DIRECTION PERPENDICULAR TO THE PLANE OF SAID DOOR IN ITS CLOSED DISPOSITION. 